Is it possible to recapsule Vyvanse into empty capsules so that I can have a lower dose but still having the capsule protect my stomach?

Explanation: I've been on Elvanse/Vyvanse 30mg on and off for two years and after a bit of experimenting I've come to the conclusion that 30mg is too much for me as I'm also autistic and get overstimulated easily so I started dissolving a capsule in water and drinking half in one day and half on the following one, achieving what's for me, a perfect 15mg dose. However for the last months I've been having stomach issues that coincide with the days I take Vyvanse - feeling of mucus stuck in throat that doesn't clear, a bit of heartburn, etc - and I think drinking the meds is what's causing it and I was wondering if I could split each Vyvanse capsule into two empty capsules so that I have that extra protection from it for my cranky stomach/throat. Is it possible?